Art of mining coal



Aug. 24, 1926, 1,597,023

E. DRENNEN ART 0F MINING COAL Filed March 22, 1924 4 Sheets-Sheet 1 abbofznuf Aug. 24 1926.

E. DRENNEN ART OF MINING C OAL Filed March 22l 1924 4 sheets-sheet s a S mw y l alkmaar Patented Aug. Z4, i926.

EVERETT BRENNEN, OF, ELKINS, WEST VIRGINIA.

ART or MINrNG COAL.

Application filed March 22, 1924. Serial No. 701,087.

rIhis application is a continuation in part of my copending application filed May 13, 1922, Serial No. 560,605.

My invention relates to improvements in the art of mining coal, in generalto that style of operating coal mines termed longwall mine and more particularly to a moditication of this system or a long-wall panel method of operation and equipment; that is, my invention contemplates in general the long-wall system but modified in 'that the working face is formed into shorter angularly disposed panels, which is conducive of better results because the workmen vand equipment are protected byy the support given to the roof by the projecting faces of the unmined area, and secondly, because for Y .O iven area a larger working face is availab e, giving maximum concentration of development and operation, with consequent minimization of the cost of Ventilating, drainage, haulage, and auxiliary mining equipment. i

In another aspect my invention combines the advantages ofthe retreating long-wall system (protection by the unmined area) with the advantages of the advancing longwall system (quick 4development of maxi-A mum production). Whether the mine iS Cle-V veloped by the advancing or by the retreating method, the workers and mining equipment, such as conveyors and loading devices, are protected by the projecting angularly disposed working faces and by the unmined seam through which the coal is always removed.

Another feature of my invention consists in 'straight-away substantially concurrent development and recovery, from one boundary to the opposite boundary; that is, my invention contemplates carrying on development or advancing in the panels in the same direction and preferably at substantially the same rate of speed as recovery or secondary mining. This expedient enables me to mine and transport a large production of coal from a small area and with minimum haulage equipment and auxiliary service (posting, ventilation, etc., etc). In other words, by my improved method, mining and transportation are carried on intensively in a relatively small area, thus keeping down to a minimum the total working area which must be maintained in a safe condition, reducing to a minimum the investment in advance development which must be idle until reached by the recovery operations, and also minimizing the total length of installed haulage equipment, whether trackage or conveyor.

In the 'accompanying drawings several modifications ofthis generalsystem of mining are illustrated as well as the system of conveying p employed therewith whereby those skilled in this particular art may readily appreciate the advantages derived from the use of this invention.

In the drawings:

Fig. l is a diagrammatic View of a coal mine which is being operated in accordance with my improved method;

Figs. 2 to 6 inclusive are similar views showing modified forms of Working faces;

Fig. 7 is a plan view showing an assembly of the face, cross and lateral conveyors;

8 isa diagrammatic view illustrating a modification of my method of mining for use where a weak roof must be contended with; and

Fig. 9 is a similar view illustrating sev eral methods of leaving supporting pillars of solid coal in rear of the mining operations.

In Fig. l there is illustrated a preferred manner of carrying out my invention. Starting from a heading or haulway 1.0, a lateral entry 11 is driven, preferably at substantially right Vangles Yto the haulway in the prese-nt embodiment of my invention, but as will hereinafter appear, my invention may be realized in certain of its aspects by driving the lateral entries at any angle to the haulway. The driving of the first lateral entry 1'1 is preferably started as soon as practicable after the haulway has been developed to a suitable point, it being an important result of my improved method that maximum daily output of coal may be very luickly attained in a relatively small area.

onsequently, development of the main, lateral and crossentries is pressed forward locally as fast as practicable in order to reach the stage of quantity product-ion of coal as soon as possible. Further development of the haulway and lateral and cross entries is lrcpt somewhat in advance of the mining operations at the working faces but not very much in advance because, as previously stated, a high output can be attained by the developn'ient ot' a very small area, as compared with previo-us practice, and it theretore, unnecessary to open up and prepare tor. mining the large areas which must be opened up under present practice, whether ot the room and pillar or ot the. long-wall system, betere production in large quantity can be reached,

rThe lateral entry ll is driven through to the opposite side et the section to be mined which in the present instance is bounded by previously mined area. [is the lateral entry il advances, cross entries are dri von 'from the opening ot the mine toward the lateral entry-ilY and in the present club diment ot' my invention these cross entries parallel to the haulway l0.

lWhen these cross entries have been developed as tar as the lateral entry ll a working tace is established across the ends oit the entries. ln this present instance the working tace is shown as composed ot plurality ot faces la angularly disposed with relation one to another and to the cross entries, thereby forming projections or piers l5 ot unmined coal which constitutes spaced supports tor the miney root and thus provide relatively sheltered spaces between the. working `faces in which men and mining equipment may operate with safety.

Any known or suitable means may be employed ior leading and carrying Vout the mined. coal. However, l prefer to employ a mechanical conveying system c-omprisiA 1' belt sectional conveyors.

cgil

.,iionld be ,o As shown diagrammatically, there is provided adjacent each tace lei a face conveyor 18, each two ot said conveyors preferably depositing the material conveyed thereby on what will be termed herein a cross conveyor i9, one ot which is` disposed in each ot the entries l2 rlhese cross conveyors may be composed ot a suitable number ot separable sections and in turn convey the material to the adjacent lateral entry l2 where they may deposit the material on cars or on smother conveyor whereupon the material. may be conveyed to the main heading and thence to the entrance ot the. mine. rllhe relation or" the tace, cross 'and lateral conveyors is shown in Fig. 7.

The working faces llt may be attacked in any approved manner tor the purpose ot breaking up and loading the coal. but the profile ot the working face should be maintained with substantially the same contiguration. This will result from retreating the Jfaces in uniform, parallel stages, as shown in broken lines on the drawing, these lines representing successive passed stages of the faces ld, The face conveyors will be advanced step by step with the faces le and the cross conveyors will be correspondingly shortened from time to time by the removal or sections.

is the faces 14 are retreating further development should go on. Thus a second lateral entry ll@L will be formed and cross entries 12L will be driven to meet it; while a third lateral entry llb may be started, the haulway l0, ot' course, being liept somewhat in advance ot other developments. It will be noted that the cross entries 12a are con tinuations ot or are in line with the cross entries ll, and it is'an important feature ot my invention that this relation ot the cross entries be maintained throughout a given section to be mined, so that all coal removed trom the working. tace from one boundary ot the section to be mined to the other` boundary, will pass through this series of longitudinally disposed parallel cross entries. This means that the working faces will be kept continuously adjacent the cross entries and a minimum amount ot shitting of mining equipment will be required. The tace conveyors will be moved only tor the purpose ot keeping up with the retreating races, but otherwise, will not be shifted.` The cross conveyor sections, as they are removed trom adjacent the working faces, may be loaded on to the remaining` portions ot the cross conveyor and thus carried back to the lateral entry and on into the advancing Cross entries l2,

By the method above described I claim, in addition to the well known advantages of long-wall mining, a special combination of features which have heretofore been peculiar to either advancing or retreating' but not common to both. That is, the sectionv to be mined is advanced in the sense that operations are started at one end ot the property near the mine entrance and development or advancing in the panels progresses continuously and iirone direction from one boundary to the other, but by withdrawing the coal through'the cross en' tries in the same direction as this development., l am enabled to work the panels by the retreating method, taking advantage ot the unmined area as protection for the conveying entries and equipment therein, and carrying on the recovery also continuously and in one direction, with the resulting economies,4 hereinbetore mentioned. It should be understood, however, that the advancing development of the section to be mined, al` though preferred for some reasons, is not the only manner in which my invention may be employed, and in its broadest aspects, particularly in reference to the angularly disposed working panels, my invention is applicable to the retreating method ot development in which the entriesare carried to the remote boundary of the section to be Lil mined before theworking face is established.

Another important advantage achieved by my method above described depends upon the fact that angular disposition of the working faces very largely increases the length of the working face as a whole, and since the rate at which coal may be mined must vary directly as the dimensions of the working face, other conditions being assumed to be adequate, it will be obvious that coal may be withdrawn from a mine having a small area developed in accordance with my. invention in quantities attainable in mines developed by known methods only by the development of areas many times greater. Among the advantages which flow from this may be mentioned the earlier attainment of maximum production because of the relatively smaller amount of develop ment necessary and reductions in such items of expense as ventilation, drainage and auxiliary equipment, which are roughly proportional to the extent of the area developed.

That part of my invention which relates tothe angular disposition of the working` faces may be realized in various ways and a few alternatives are shown in Figs. 2 to 6. In these figures the lateral entries l2 are disposed obliquely to the haulageway l0, an arrangement which does not realize all of the advantages of my improved method but serves to illustrate the adaptability to various kinds of development of the feature of angularly disposed working faces. As shown, these working faces may be disposed at right angles to one another or at any other angle less thanlSO degrees, and in some situations it may be desired to have the working faces of different lengths, as shown in Fig. 5. Another ymodification is shown in Fig. 6, in which the working face is broken up into shorter faces of serrations ltb and the face conveyor 18" eX- tends across the whole working face. ln this embodiment a certain amount of protection will be afforded by the projecting points to a workman operating between the conveyor and the face.

n mines which have a more than usual weak roof, a modification of my method may be employed to advantage. (See Fig. 8.) In this modification the lateral cross entries and the working faces are formed in the rmanner previously described with reference to Fig. l, but instead of working all of the faces simultaneously alternate pairs and the corresponding cross entries will be worked to remove the coal in strips, as shown. Thereupon the roof may be permitted or caused to fall into the mined strips andthe remaining alternate pairs of faces and cross entries may then be worked to remove the rest of the coal under the protection of the pack walls automatically formedbby the fallen, broken material of the roof. I

In Fig. modication directedrto the end of furnishing a support for the roof at the expense of a little coal left unmined. As shown, in

Vtaking awaythe coal, a portion may be left unmined, either in the form of triangular pillars 15a, square pillars 15b or asa solid unbroken wall 15C.

Having thus described my invention, what I claim is:

l. The method of mining coal which consists in forming a pair of diverging working faces, driving an entry through the unmined seam from the intersection of said working faces, and conveying coal from said working faces to and through said entry, the progression of the working faces being in the same direction las the conveyance of coal through said entry.

2. rlhe method of mining coal which consists in forming a series of working'faces in zig-zag relation across one end of a panel to be mined, thus providing Va series of jutting piers of unmined coal with sheltered working areas between the piers, driving substantially parallel entries through the unmined seam from the intersections of said working faces remote from the apeXes lof said piers, and,k conveying coal from said working faces to and through said entries, the progression of the working faces being in the same direct-.ion as the conveyance of coal through said entries.

3. The method of mining coal which con sists in forming a series of working faces in Zig-Zag relation across one end of a panel to be mined, thus providing a series of jutting piers of unminedcoal with sheltered working areas between the piers, driving substantially parallel entries longitudinally through the unmined panel from the intersections of said working faces remote from the apexes of said piers, conveying coal from said working faces to and through said entries, the progression ofthe working faces being in the same direction as the conveyance of coal through said entries, and driving lateral entries from time to time and at convenient points to intersect said first-mentioned entries and collect the mined coal from said entries, whereby development and mining of the panel proceed continuously and simultaneously until all of the coal in the panel has been recovered.

4L, The method of mining a seam of coal having a weak roof, which consists in forming a series of working faces in zig-zag relation across one end of a panel to be mined, thus providing a series of jutting piers of unmined coal with sheltered working areas between the piers, driving substantially parallel entries through the un'- mined panel from the intersections of said 9 there is illustrated another lGO Working, faces remote from the apeX'es of said piers, recovering coal from alternate pairs of said Working faces and conveying the coal to rnd through the adjacent entries, permitting thereof to fall into the strips thus mined, and then recovering the coal from the remaining zilternate pairs of work ing faces and conveying the coal to and through the adjacent entries under the protecti'on of the mined strips, the progressie''n of the yWorking faces in each stage being* inthe 'saine Y direction as the conveyance of coal throng-i1 said entries.

The `foregoing speciictibn signed 't] New York, N. Y.,'thi's 29th day of'Feb'rLrary, 1924.

EVERETT @RENNEN reilen 'ro-ef in thelpre'vieusly 10 

